1. Set oven to 375 degrees F (190 degrees C).
2. Scrub the potatoes with an abrasive plastic pad reserved for vegetables, and rinse. Quarter the potatoes.
3. Coat a baking dish with butter, or nonstick cooking spray
4. Place potatoes in a single layer in prepared dish, with onion on top.
5. In a bowl, combine melted butter, honey, mustard, salt and pepper. Drizzle the mixture over the potatoes and onion.
6. Roast in the oven for 35 minutes or until tender, stirring halfway through the cooking time.